Strand – Energy and forces

Strand Unit – Heat

Class – 3rd – 6th

Air vs Water (Which is the better conductor of heat?)

Prior knowledge required by students

Air is made up of different gases, water is a liquid and has different properties. Both of them can flow but both are not visible. 

Stage 1

Stimulus questions to engage the students and get them interested

Why are the radiators in our homes made from metal?

Why is the handle on a frying pan or saucepan made from rubber?

If you open a fridge door, why does it feel so cool and refreshing on a very warm day?

Listen to an audio clip of the children questioning each other.               

Stage 2

The Experiment

Materials needed – (candle, 2 latex balloons, matches, water)

The children have to investigate whether water is a better conductor of heat than air.  Take a look at the following video to see how the experiment transpires. Divide the class into groups of two or four and before carrying out the experiment, make sure you record each groups’ predictions.

Video – conduction

Stage 3

Learning outcomes

Discuss each groups’ findings and ask the following questions

Why did one balloon burst while the other did not when it came into contact with the flame?

Listen to an audio clip of the children’s findings            

Conclusion

Revisit the predictions made in stage 2 and see whos predictions were closest to the actual outcome.  Discuss how the children worked like scientists where they answered some research questions, planned an experiment and then carried out the experiment.